Purpose: Sight threatening uveitis may require long term use of systemic immunosuppressants. In some patients,aggressive systemic immunosuppressive therapy fails to control inflammation and can lead to serious side effects. Oral Cyclosporin A (CsA) has been shown in several human trials to be effective in treating chronic uveitis. This pilot study will assess the safety, and to some extent efficacy, of a novel intraocular CsA sustained delivery device in patients with active inflammation and poor visual acuity in one eye despite immunosuppressant therapy. Methods: It is anticipated that five patients will be recruited into the study at Duke, and an additional 5 will be recruited at the National Eye Institute. Patients are randomly assigned to receive in one eye a 1 or 2 mg CsA implant releasing at either 0.8 g/day or 1.4 g/day respectively. Safety of the CsA implant, the primary study outcome, is determined by serial ophthalmological examinations, fluorescein angiography, and electroretinography. Secondary outcomes including a change from baseline in the ocular inflammation and visual acuity, and the need for concomitant anti-inflammatory medications are determined by ophthalmological examination and patient history, respectively. Results: To date 4 patients have been enrolled at the Duke Eye Center, and 3 have been recruited at the NEI. Of the 4 patients recruited at Duke, 1 developed a transient vitreous hemorrhage that was present immediately after surgery and which cleared spontaneously. One patient developed transient hypotony in the postoperative period which also resolved spontaneously. There were no other surgically related complications. One patient underwent uncomplicated cataract extraction in the cyclosporine treated eye, for a cataract which was present prior to cyclosporine drug device implantation. Each of the four patients enrolled at Duke is still being actively followed to accrue additional safety and efficacy data. Conclusions It has been feasible to recruit and follow patients in this pilot trial. Complications related to device implantation have been minimal. Additional safety and efficacy data are still being collected.